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Whenever I turn on my AC during the summer time the engine shakes alot and seems like the whole car is also shaking when I sti idle. If the I rev it to one rpm then then engine is smooth and does not shake anymore.

This only happens when I have the AC on. Even without the AC on though you can still feel a little bit of shakiness but then I think that is just how a rotor engine is.

My idle rpm is about half or maybe three quarters close to one rpm when sitting idled. I was going to take it to the dealer but did not know how much it was going to cost because I just got done paying my school tuition.

Where should the idle be when your 8 is idled and does it shake bad when you turn on your AC.

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Yeah, I remembered that when I first bought this car. I had trouble telling if the car was even running or not. I just had my engine replaced though. You would think that they would've noticed a bad motor mount then. Calling service rep now.

I experience the exact same problem, only mine is rough without the AC on, just gets noticably worse when it is on. It comes and goes and only happens when the car is fully warmed up. When you are outide the car you can hear a 'popping' from the exhaust like it is missing or backfiring. As soon as you give it any gas at all it is fine. I can see a bad motor mount making it worse in the cabin, but causing the problem? I had a sorta similar issue with my Talon and it was the little servo that moved the throttle plate at idle. Obviously our electronic throttle would not have that issue, just saying.

I have had this problem for some time now and at first I didn't mind but it has been getting progressively worse. When I got the recall letter, I thought great I can finally get this fixed for good. I am still trying, see the 4206 thread. Hope you have better luck with the dealer!

Dropped my car off this morning and got a call back pretty quickly from the shop foreman giving me crap about the Penzoil 2-stroke oil that I keep under the hood next to the washer fluid resevior. I was in a meeting so I didn't take his call but from the sound of his voicemail it sounded like he thought I was using it as the engine oil. He gave me the whole rundown about how the Renesis uses oil to build compression and that I should call him back immediately if I had any questions. Haha. Think I should bother calling? His exact quote was "we have your car down here and I saw this Penzoil oil and have some serious concerns". I wonder what the dealerships take on premixing would be....

Just got the call from my service advisor to pick up the car. According to him it was a bad spark plug. He said that the reman engines installed in the recall come with the spark plugs already installed so they didn't check them and one of the plugs wasn't firing correctly. He said he had his QC Foreman go over the car and test drive it and that it "got a clean bill of health". We'll see when I go pick it up....

Same issue here. Reman replacement ... idles like crap. Pulls strong but idle sux. They are breaking motor mounts when they are popping these things in and out or they are bypassing step 20 of the manual regarding engine replacement which says, and I quote,

"20. Perform the on-road test and verify that there is no vibration or noise."

58854 leading spark plug onto trailing side diagnose and inspected for any DTC's prsent. Inpected spark plugs and found one leading spark plug onto trailing side from number 2 rotory. During rotory engine replacement, new reman rotory came with new spark plugs. Replaced two trailing spark plugs and checked rotory engine idle speed for proper operation. Inspected mode 6 drive cycle readings for assurance. Note: please be adviced, found quart bottle of 2 cycle synthetic oil inside engine compartment. It is strong recommended not to use synthetic oil for rotory engines due to higher flash point for burning oil properly. Damage to converter efficiency can result.

I have no idea what a good amount of this means, but they replaced the two trailing plugs. The engine is still not as smooth at idle as it should be. Mine seems to idle around 850-900 RPMs. If I blip it up to 1000, it's perfectly smooth, but there's still a little vibration at its natural idle. Overall, I'm pretty disappointed.

Note: please be adviced, found quart bottle of 2 cycle synthetic oil inside engine compartment. It is strong recommended not to use synthetic oil for rotory engines due to higher flash point for burning oil properly. Damage to converter efficiency can result.

HAHAHAHAHAHAHAHAHAHAHAHAHAHAAHA
d!@#!@#@!#@!#!@#@!%$!#$!@#

Well, they replaced the engine... they should replace the computer next... not flash but physically replace. do that and that should take care of it. if not, then.... its something in the body vibrating, and that would be a real bitch...

Location: In the hills between San Miguel and Parkfield - "up in the boonie lands", Central Coast of California, Wine Country

Posts: 734

If the vibration only occurs when your air conditioner is on and especially when it's on high, its not the engine - if engine was bad it would vibrate all time, it's not the sparks - they would be bad all the time - instead check the airconditer fan - you have something in the fan compartment like an acorn or small rock - it is messing with the fan and the fan can cause the whole system to vibrate you get to it from the hood area - ask tech for help and after you clear the fan also pull the glove box and check the filter area, you may have a small evil visitor that put the acorn or rock in the fan! Do not kill it! A dead mouse is much worse than a live one, especially in the air conditioner!
Use a glue trap so you can remove it, if caught!

If the vibration only occurs when your air conditioner is on and especially when it's on high, its not the engine - if engine was bad it would vibrate all time, it's not the sparks - they would be bad all the time...!

It vibrates all the time, just worse with the airconditioner on. Thanks for the suggestion though. I'll poke around a bit.

I may be making a bigger deal out of this than is necessary, but I remember when I first got this car how I couldn't tell that it was running when I was stopped at a stoplight because it was so smooth. I just want that back...